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FWIW, I'm not actually an electricial contractor, trying to get into training for the industry ATM, this picture was nicked from a UK forum

These things have a heater in (the black lump) that is rated at somewhere between 7kw - 11kw (thats at 240v BTW), if you look at the cable supplying it, and compare it to the internal cabling, you can see that its undersized, also flexible cable shouldn't be used for fixed wiring, and where it enters the unit without use of a gland, the watertightness is no more... also having the cable hanging loose in the shower area is... not good

- Adam_151
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Joined: Jul 2002
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Gidday there Adam,
Welcome to the group!. [Linked Image]
I'd like to say that there is no way that wiring supplying that unit will carry the current required to operate it.
We have the same units over here in New Zealand and nothing short of 6mm2 wire will do for a set-up like this.
I'd also be interested to see what sort of fusing was used at the feeding end. [Linked Image]

Joined: Jul 2004
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Ouch. Just plain 'ouch'.

Notwithstanding the fact that flex can't be used for fixed wiring and it's majorly undersized, when it eventually melts down, if it doesn't short circuit right then, there are going to be exposed burned out wires in the shower area, not nice. I second Trumpy's wish to see the feed end of this, I bet it's just as scary (I am thinking either wired into a socket on a 30-32A ring, or more likely 13amp plug with a piece of nail as the 'fuse')

Joined: Dec 2001
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Hm... guessing the wiring at the top is 6mm2 I'd say the home owner wiring is at max. 1.5mm2, rather 1mm2. OUCH!

Let me guess. The typical rating of such a beast is 7-9kW. Assuming a resistive load and an optimistic voltage of 240V that's 29-37.5amps. A 32A breaker probably wouldn't trip at all.
Go figure...

Joined: Jul 2002
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Chipmunk,
You're dead right, mate, that is a flex!. [Linked Image]
Sorry, I'd forgotten that in the UK, all the fixed wiring cables are grey sheathed.(AFAIK)
This takes on a whole new meaning of wrong now.
I hope that this was disconnected when it was found, this could cause someone some real harm. [Linked Image]

{Edit: I always thought that the supply cable was supposed to enter the bottom of the unit, through some sort of gland to maintain the IPX4 ingress protection rating?.}


[This message has been edited by Trumpy (edited 03-24-2006).]

Joined: Mar 2006
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Sorry, I'd forgotten that in the UK, all the fixed wiring cables are grey sheathed.(AFAIK)

Not exactly true, Twin & Earth which is used for most domestic wireing is usally grey on the outside, it was available in white as well, but as part of the colour change white T&E is the special low fume stuff, and grey is the normal stuff

years ago VIR (rubber) cables were used which were black on the outside, some modern cables are black, split concentric and SWA (steel wire amoured) are both black.

MICC can be bare copper on the outside, or can be white, orange, black, and probably many other colours besides, and firetuff is usually red (used for firealarms, so it can be seen at a glance what its for)

Different types of cable used in the UK can be seen here: http://www.tlc-direct.co.uk/Main_Index/Cable_Index/index.html

Joined: Jul 2002
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Adam,
Have you seen the area used by us guys from outside of the US?.
It gets a lot of use.
Check this out and enjoy .

Joined: Dec 2005
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I'm supprised that the 1.5mm² flex wire has not discoloured from heat yet, nor are the choc bloc connecters which have usually steel sleeves instead of brass in them.
If that is an 7 to 11 kW heating element, the fixed wiring should be at least 6mm². not a piece of flex.
I wonder what is on the other end of that flex. a 13 Amp plug with a drillbit as fuse? [Linked Image]
you wonder sometimes that not more houses burn down or people get electrocuted.
The flex. earth wire looks like that it is not lugged off properly either.


The product of rotation, excitation and flux produces electricty.
Joined: Mar 2006
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You'd be supprised how much they can take, it'll get a bit warm and go brittle, but not start melting in a massive way, its amazing the tolerances things have...

On another note, I need to install one of these units at home (with 10mm² wire [Linked Image] ), bloody regulations make it difficult for DIYers to do much these days, sorry, ranting

Joined: Aug 2001
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Welcome to ECN Adam,

It also appears to me that the "entry point" for the undersized flex has been created by just hacking a hole in the side of the unit.

I thought it was bad when I found a shower wired from just the pull-switch to the unit with 2.5 T&E, but this one beats that by a long chalk!


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